Transmission fluid (viz. oil), especially of automatic transmissions, develops considerable heat build-up during the operation of a motor vehicle. For this reason, oil cooling systems are provided which pump transmission oil by means of cooling lines, out from the transmission housing through a transmission oil cooler tank, which may be an auxiliary unit or an integral part of the radiator of a water cooling system. The cooler core includes one or more finned tubes, located so air passing through the radiator and neighboring circulating engine coolant will cool the oil. Metal lines connect transmission outlet and inlet ports to cooler inlet and outlet ports.
Transmission oil is drained and replaced, and the cooling system flushed, when the transmission is serviced and also periodically as a part of good motor vehicle maintenance practice. For this purpose, equipment such as the Hayden Trans-Tool T-1090-HD oil cooler and line flusher can be employed. Such equipment comes with hoses and fittings for attachment to standard 5/16" hex nut, factory vehicle oil cooling system fittings. An adapter such as the Hayden Trans-Tool HSK-250 Quick-Connect.TM. coupler (U.S. Pat. No. 4,073,512) can be used for connection of 5/16" factory cooler fittings, male and female, to hoses of conventional flushers, without the need to cut through metal lines. However, no means exists to connect the hoses of the flusher to metal lines terminating in a banjo-style fitting.